Introduction Hirschsprungdisease (HD) is a congenital malformation characterized by absence of ganglion cells in the myenteric and submucosal plexuses of the distal intestine ( Martucciello et al . 2000 ). It is thought to be caused by disordered

polymorphisms have been shown to be under-represented in Hirschsprung's disease (HSCR, OMIM 142623) patients compared with controls, thus suggesting that they might protect against the development of HSCR ( Borrego et al . 1999 ). The RET -G691S polymorphism

clinically silent. Importantly, the T338I mutation has been previously described in Hirschsprungdisease ( Fitze et al . 2002 ), which does not belongs to the clinical history of either our patient or her family members, including those harbouring the same

Serisha Moodley, Frank Weber and Lois M Mulligan

RET-targeted therapies, and preclinical and early clinical trials of RET inhibition in these contexts are already underway ( Redaelli et al. 2018 ).
RET loss of function mutations are found in familial forms of Hirschsprungdisease, a congenital